This sink tapers from top to bottom by 1/4"Wall Thickness : 3/4"For Under Mount (countertop Over edge of sink) installation only.Heat resistant up to 350'' F. This sink has been tested and will not crack due to heat exposure from a pot / pan up to 350'' F hot.3 1/2" Rear Center drain.Due to the organic nature of the fireclay, material dimensions may vary by 1/8" of an inch. We recommend having the sink on location to trace and measure for countertop and cabinet cut outs. Furthermore , minor imperfections may appear. These are not defects; this is what makes each sink uniquely its own. Defective sinks will not pass our quality control inspection and would be recycled into a new sink at the factory.This sink is constructed of solid high-grade fireclay�material�using high pressure casting, ensuring durability, longevity, and resilience�to�acids, alkali''s, scratches, and chipping.Certified by Uniform Plumbing Code (cUPC)It is required to support the sink from beneath regardless of how it is installed. This ensures that the entire weight of the sink is properly supported.